Benjamin,
On Wed, Aug 2, 2023 at 12:20 AM Cong Yang
[off-list ref] wrote:
The ili9882t is a TDDI IC (Touch with Display Driver). The
datasheet specifies there should be 60ms between touch SDA
sleep and panel RESX. Doug's series[1] allows panels and
touchscreens to power on/off together, so we can add the 65 ms
delay in i2c_hid_core_suspend before panel_unprepare.
Because ili9882t touchscrgeen is a panel follower, and
needs to use vccio-supply instead of vcc33-supply, so set
it NULL to ili9882t_chip_data, then not use vcc33 regulator.
[1]: https://lore.kernel.org/all/20230727171750.633410-1-dianders@chromium.org (local)
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Cong Yang <redacted>
---
drivers/hid/i2c-hid/i2c-hid-of-elan.c | 50 ++++++++++++++++++++-------
1 file changed, 38 insertions(+), 12 deletions(-)
quoted hunk ↗ jump to hunk
diff --git a/drivers/hid/i2c-hid/i2c-hid-of-elan.c b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
index 029045d9661c..31abab57ad44 100644
--- a/drivers/hid/i2c-hid/i2c-hid-of-elan.c
+++ b/drivers/hid/i2c-hid/i2c-hid-of-elan.c
@@ -18,9 +18,11 @@
#include "i2c-hid.h"
struct elan_i2c_hid_chip_data {
- unsigned int post_gpio_reset_delay_ms;
+ unsigned int post_gpio_reset_on_delay_ms;
+ unsigned int post_gpio_reset_off_delay_ms;
unsigned int post_power_delay_ms;
u16 hid_descriptor_address;
+ const char *main_supply_name;
};
struct i2c_hid_of_elan {@@ -38,9 +40,11 @@ static int elan_i2c_hid_power_up(struct i2chid_ops *ops)
container_of(ops, struct i2c_hid_of_elan, ops);
int ret;
- ret = regulator_enable(ihid_elan->vcc33);
- if (ret)
- return ret;
+ if (ihid_elan->vcc33) {
+ ret = regulator_enable(ihid_elan->vcc33);
+ if (ret)
+ return ret;
+ }
ret = regulator_enable(ihid_elan->vccio);
if (ret) {@@ -52,8 +56,8 @@ static int elan_i2c_hid_power_up(struct i2chid_ops *ops)
msleep(ihid_elan->chip_data->post_power_delay_ms);
gpiod_set_value_cansleep(ihid_elan->reset_gpio, 0);
- if (ihid_elan->chip_data->post_gpio_reset_delay_ms)
- msleep(ihid_elan->chip_data->post_gpio_reset_delay_ms);
+ if (ihid_elan->chip_data->post_gpio_reset_on_delay_ms)
+ msleep(ihid_elan->chip_data->post_gpio_reset_on_delay_ms);
return 0;
}@@ -64,8 +68,12 @@ static void elan_i2c_hid_power_down(struct i2chid_ops *ops)
container_of(ops, struct i2c_hid_of_elan, ops);
gpiod_set_value_cansleep(ihid_elan->reset_gpio, 1);
+ if (ihid_elan->chip_data->post_gpio_reset_off_delay_ms)
+ msleep(ihid_elan->chip_data->post_gpio_reset_off_delay_ms);
+
regulator_disable(ihid_elan->vccio);
- regulator_disable(ihid_elan->vcc33);
+ if (ihid_elan->vcc33)
+ regulator_disable(ihid_elan->vcc33);
}
static int i2c_hid_of_elan_probe(struct i2c_client *client)@@ -89,24 +97,42 @@ static int i2c_hid_of_elan_probe(struct i2c_client *client)
if (IS_ERR(ihid_elan->vccio))
return PTR_ERR(ihid_elan->vccio);
- ihid_elan->vcc33 = devm_regulator_get(&client->dev, "vcc33");
- if (IS_ERR(ihid_elan->vcc33))
- return PTR_ERR(ihid_elan->vcc33);
-
ihid_elan->chip_data = device_get_match_data(&client->dev);
+ if (ihid_elan->chip_data->main_supply_name) {
+ ihid_elan->vcc33 = devm_regulator_get(&client->dev,
+ ihid_elan->chip_data->main_supply_name);
+ if (IS_ERR(ihid_elan->vcc33))
+ return PTR_ERR(ihid_elan->vcc33);
+ }
+
return i2c_hid_core_probe(client, &ihid_elan->ops,
ihid_elan->chip_data->hid_descriptor_address, 0);
}
static const struct elan_i2c_hid_chip_data elan_ekth6915_chip_data = {
.post_power_delay_ms = 1,
- .post_gpio_reset_delay_ms = 300,
+ .post_gpio_reset_on_delay_ms = 300,
+ .hid_descriptor_address = 0x0001,
+ .main_supply_name = "vcc33",
+};
+
+static const struct elan_i2c_hid_chip_data ilitek_ili9882t_chip_data = {
+ .post_power_delay_ms = 1,
+ .post_gpio_reset_on_delay_ms = 200,
+ .post_gpio_reset_off_delay_ms = 65,
.hid_descriptor_address = 0x0001,
+ /*
+ * this touchscreen is tightly integrated with the panel and assumes
+ * that the relevant power rails (other than the IO rail) have already
+ * been turned on by the panel driver because we're a panel follower.
+ */
+ .main_supply_name = NULL,
};
static const struct of_device_id elan_i2c_hid_of_match[] = {
{ .compatible = "elan,ekth6915", .data = &elan_ekth6915_chip_data },
+ { .compatible = "ilitek,ili9882t", .data = &ilitek_ili9882t_chip_data },
Logically, this patch depends on the panel-follower series that's now
landed in drm-misc-next. With your Ack, I'm willing to land these two
patches into drm-misc-next too. Other options:
a) We could land the two patches in the i2c-hid tree since they don't
appear to conflict. The touchscreen won't actually function until the
patches meetup in linux-next but I don't think they'll give any
compile errors (I haven't double-checked that, but I can). ...though
it's possible that the dt bindings might generate errors? Again, I can
investigate if we want to go this way.
b) We can snooze this for a few months and you can pick it to i2c-hid
when my series reaches mainline.
Let me know how you'd like to proceed.
-Doug